Adding NonFatal and Unsafe to scala.concurrent.impl

2 files changed, 68 insertions, 0 deletions

diff --git a/src/library/scala/concurrent/impl/NonFatal.scala b/src/library/scala/concurrent/impl/NonFatal.scala
new file mode 100644
index 0000000000..ac0cddaf1b
--- /dev/null
+++ b/src/library/scala/concurrent/impl/NonFatal.scala
@@ -0,0 +1,36 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2011, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.concurrent.impl
+
+/**
+ * Extractor of non-fatal Throwables. Will not match fatal errors
+ * like VirtualMachineError (OutOfMemoryError)
+ * ThreadDeath, LinkageError and InterruptedException.
+ * StackOverflowError is matched, i.e. considered non-fatal.
+ *
+ * Usage to catch all harmless throwables:
+ * {{{
+ *   try {
+ *     // dangerous stuff
+ *   } catch {
+ *     case NonFatal(e) => log.error(e, "Something not that bad")
+ *   }
+ * }}}
+ */
+object NonFatal {
+
+  def unapply(t: Throwable): Option[Throwable] = t match {
+    case e: StackOverflowError ⇒ Some(e) // StackOverflowError ok even though it is a VirtualMachineError
+    // VirtualMachineError includes OutOfMemoryError and other fatal errors
+    case _: VirtualMachineError | _: ThreadDeath | _: InterruptedException | _: LinkageError ⇒ None
+    case e ⇒ Some(e)
+  }
+
+}
+
diff --git a/src/library/scala/concurrent/impl/Unsafe.java b/src/library/scala/concurrent/impl/Unsafe.java
new file mode 100644
index 0000000000..3c695c3905
--- /dev/null
+++ b/src/library/scala/concurrent/impl/Unsafe.java
@@ -0,0 +1,32 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2011, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+
+package scala.concurrent.impl;
+
+import java.lang.reflect.Field;
+
+public final class Unsafe {
+    public final static sun.misc.Unsafe instance;
+    static {
+        try {
+            sun.misc.Unsafe found = null;
+            for(Field field : sun.misc.Unsafe.class.getDeclaredFields()) {
+              if (field.getType() == sun.misc.Unsafe.class) {
+                field.setAccessible(true);
+                found = (sun.misc.Unsafe) field.get(null);
+                break;
+              }
+            }
+            if (found == null) throw new IllegalStateException("Can't find instance of sun.misc.Unsafe");
+            else instance = found;
+        } catch(Throwable t) {
+          throw new ExceptionInInitializerError(t);
+        }
+    }
+}